1. Field of the Invention
The present invention relates to the extraction of gases and gas particulates. More particularly, the present invention the relates to flexible ducts for removing or extracting gases from a given area. More particularly still, the present invention the relates to flexible ducts having supports for positioning the ducts. More particularly still, the present invention the relates to flexible ducts having internal supports.
2. Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 37 CFR 1.98.
Hoses, ducts, and conduits in various sizes and configurations are commonly utilized for conveying, routing, and directing various substances and objects. For example, many factories use machines and equipment in welding which create unhealthy gases, fumes, or vapors which must be immediately extracted from the building. Those in need of extracting harmful gases from a building usually use flexible ducts to do so. The flexible ducts are connected to some kind of suction source that removes the harmful gases from the area.
Ducts are made to be flexible so that the position of the duct opening can be changed so as to optimally extract harmful gases from the area. In the past, it has been quite a challenge to keep a flexible duct in a fixed position. Prior art has attempted to remedy the problem of fixedly positioning a flexible duct by adding support arms. Theses support arms are either located inside the duct or outside the duct.
For example, U.S. Pat. Nos. 6,503,139, issued on Jan. 7, 2003 to Coral, describes an external duct support on a conduit that includes a rotary fitting, in two segments, elbow-connected to each other. Each of the segments has an articulate mechanism that includes a pair of U-section bars connected to each other in the form of an articulated parallelogram by means of two articulated elements. A spiral compression spring is housed between each pair of bars and is compressed between a disk that is integral with one of the bars and a flange that slides along a threaded rod. The flange is locked on the rod by means of a nut. The rod is connected to a lever member pivoting on one of the articulated elements so as to adjust the action of the spring as a function of the angular position of the relative segment with respect to the articulated element.
U.S. Pat. No. 5,536,206, issued on Jul. 16, 1996 to Bodmer et al., describes an external duct support adapted for concentrated sources of fumes and particulate matter that includes an elongated duct connected at one end to a vacuum source and adapted to be supported by a wall bracket or a portable console and a fume collection hood at the opposite end of the duct. One or more flexible joints are interposed in the duct between the support bracket and the hood. Joint support mechanisms for each flexible joint include opposed pairs of pivotally connected arms which interconnect rigid sections of duct on each side of the flexible joint. The connections between the arms of each set include a friction clutch and a ratchet-and-pawl mechanism which permits free movement of the flexible joints in a direction which is opposite that which the hood would move under its own weight while providing for counterbalancing the weight of the apparatus distal of the support bracket and a positive force required to position the hood precisely in the other direction. The friction clutch and ratchet-and-pawl mechanism is interposed between the arms of each set of arms about a pivot connection formed by a bolt and nut assembly, which may be adjusted to change the friction force required to slip the clutches of each joint support mechanism.
U.S. Pat. No. 6,354,937, issued on Mar. 12, 2002 to Crook, describes a sleeve assembly for supporting flexible duct. The assembly includes a frame with first and second frame sections. The frame sections are secured together by fastener subassemblies. The sleeve assembly accommodates flexible duct in various angular and straight configurations. The frame can comprise various suitable materials and skeletal or solid-exterior construction. The sleeve assembly is adapted for various installations in air distribution systems of heating, ventilating and air conditioning systems.
U.S. Pat. No. 2,810,400, issued on Oct. 22, 1957 to Hewitt et al., describes the wrapping of a flexible wire around the exterior of the duct. The wire is wound around the exterior of the duct in a spiral fashion. Material strips join each of the wires in an overlapped arrangement.
U.S. Pat. No. 2,804,095, issued on Aug. 27, 1957 to Schauenburg, describes an air duct whereby the duct is supported between a pair of longitudinal rods. Clamps are provided over the exterior of the surface of ducts so as to join with the rods for supporting the ducts in a desired configuration.
While these external supports for ducts have served a certain function, they have created the problem of being bulky and cumbersome. The supporting parts of these external supports are exposed to dust and to particulate matter in the air which causes the parts to get dirty and malfunction.
As a way to avoid the shortcomings of external supports for duct, the prior art has attempted to place the supporting members inside the ducts. For example, U.S. Pat. No. 3,818,817, issued on Jun. 25, 1974 to Nederman, describes an apparatus for removing noxious gases from a work area that has internal support areas. The apparatus comprises a suction fan, a flexible tubing connected to the suction part of the fan, a suction casing mounted at the tube end and provided within the tube, a lever system which consists of two lever arms of which one arm at one end is connected to the suction part of the fan and at the other end is connected to one end of the other arm, which is further connected to the suction casing.
U.S. Pat. No. 5,482,505, issued on Jan. 9, 1986 to Hedlund, describes an arrangement for the extraction of harmful gases from workplaces that has an internal support for the duct. The arrangement has a carrier arm system that has at least two arms connected telescopically with each other so that the carrier arm system can be given different lengths, whereby the carrier arm system is swivelable around a horizontal spindle so that it can be swivelled in a vertical direction and placed in different positions between a downward-directed, preferably substantially vertical, end position and an outward-directed, preferably substantially horizontal, end position. In order to permit the necessary balancing of both the swivelling and positioning of the carrier arm system and the telescoping function of the arms of the carrier arm system when the carrier arm system is swivelled within a large sector, at least one first device is arranged to generate balancing forces in order to facilitate swivelling of the carrier arm system in the vertical direction between the end positions and/or to facilitate the retention of the carrier arm system in set positions between the end positions. At least one second device is arranged to generate balancing forces which allow the arms of the carrier arm system to remain in the positions relative to each other that they were given by the telescopic function, at least when the carrier arm system is directed substantially downwards.
U.S. Pat. No. 5,738,148, issued on Apr. 14, 1998 to Coral et al., describes a hose with external supports comprising two flexible portions connected respectively to the suction unit and to the fume-conveyor element or hood, and a rectilinear portion which is articulated to the suction unit and the hood. The rectilinear portion comprises two rigid tubes between which is disposed an extensible bellows-type tube. Rigid tubes are held co-axial by a pair of rectilinear guides fixed to one of the rigid tubes and slidably engaging on a pair of fixed slides on the other rigid tube. The two rigid tubes are, finally, connected by a tension spring the action of which is braked by two friction disks disposed between the guides and the slides.
U.S. Pat. No. 5,527,217, issued on Jun. 18, 1996 to Engstrom, describes an adjustable device for exhaustion and/or supply of gases and gas-supported particles that has internal supporting members for the duct. The device comprises at least one exhaustion and/or supply conduit which is pivotable in at least a vertical direction, whereby at least one force-producing balancing device is provided for balancing the exhaustion and/or supply conduit. In order to provide at such an adjustable device that the balancing device generates balancing forces which correspond with the correct balancing requirement, the force-producing balancing device cooperates with a compensating device which compensates for the differences between the balancing force that the force-producing balancing device exerts on the exhaustion and/or supply conduit and the force required for balancing the exhaustion and/or supply conduit in substantially all its positions.
U.S. Pat. No. 5,499,946, issued on Mar. 19, 1996 to Valkering, describes a device for exhausting gases or the like that has internal support members. The internal support members comprise a support and at least one exhaustion tube movably mounted to the support and having a frame which is connected to the support in a manner pivotable at least in vertical direction. The frame is provided with a balancing mechanism for the exhaustion tube. The balancing mechanism comprises a cable with a draw spring. The cable is guided between the support and the frame such that there are formed at least two cable portions to create two force components producing an opposite variable torque around the pivot point of the frame such that the balancing torques, counteracting the gravitational torque, are produced.
U.S. Pat. No. 6,604,549, issued on Aug. 12, 2003 to Gaughier et al., describes a device for fixing a tubular element in a cavity. This device is made up of hoops made of an elastically flexible material disposed in cross-sectional planes of the cavity. The device is characterized in that, along the longitudinal axis of the cavity, the hoops are secured together by a flexible longitudinal support and are interconnected by a flexible membrane.
U.S. Pat. No. 3,716,077, issued on Feb. 13, 1973 to Sherman et al., describes a flexible insulated air duct formed by wrapping blanket insulation about a helically wound wire-like elongate tubular skeleton wherein the opposite ends of the helical windings are closed wound and secured together to form rigid collars of different diameters to define male and female connections whereby sections of such duct may be axially connected on to another.
All of these prior art internal support ducts have a common problem, i.e., that the internal support members obstruct the flow of air and also collect dust over time, further obstructing the flow of air through the duct. This is especially true when the internal support mechanisms are cumbersome and bulky.
There is a need for a flexible duct support that is less cumbersome and bulky. Moreover, there is a need for a flexible duct support that is lightweight, easy to manufacture, and inexpensive. Furthermore, there is a need for an internal flexible duct support that minimizes the restriction of air flow.
It is an object of the present invention to provide a support for a flexible duct that connects to air systems.
It is another object of the present invention to provide a support for a flexible duct that maintains the flexible duct in its desired location in a manner that is convenient to the operator.
It is yet another object of the present invention to provide a support for a flexible duct that is lightweight.
It is another object of the present invention to provide a support for a flexible duct that minimizes the flow obstruction and turbulence of gases traveling through the interior of a flexible duct.
It is another object of the present invention to provide a support for a flexible duct that serves to reduce the suction power required by the vacuum system.
It is another object of the present invention to provide a support for a flexible duct that accommodates the many types of hoses, ducts and conduits.
It is yet another object of the present invention to provide a support for a flexible duct that is formed so as to accommodate any size and diameter of flexible duct.
These and other objects and advantages of the present invention will become apparent from a reading of the attached specification and appended claims.